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1.
J Infect Dis ; 217(3): 381-392, 2018 01 17.
Article in English | MEDLINE | ID: mdl-29309618

ABSTRACT

Background: Little is known about T cells that respond to human rhinovirus in vivo, due to timing of infection, viral diversity, and complex T-cell specificities. We tracked circulating CD4+ T cells with identical epitope specificities that responded to intranasal challenge with rhinovirus (RV)-A39, and we assessed T-cell signatures in the nose. Methods: Cells were monitored using a mixture of 2 capsid-specific major histocompatibility complex II tetramers over a 7-week period, before and after RV-A39 challenge, in 16 human leukocyte antigen-DR4+ subjects who participated in a trial of Bifidobacterium lactis (Bl-04) supplementation. Results: Pre-existing tetramer+ T cells were linked to delayed viral shedding, enriched for activated CCR5+ Th1 effectors, and included a minor interleukin-21+ T follicular helper cell subset. After RV challenge, expansion and activation of virus-specific CCR5+ Th1 effectors was restricted to subjects who had a rise in neutralizing antibodies, and tetramer-negative CCR5+ effector memory types were comodulated. In the nose, CXCR3-CCR5+ T cells present during acute infection were activated effector memory type, whereas CXCR3+ cells were central memory type, and cognate chemokine ligands were elevated over baseline. Probiotic had no T-cell effects. Conclusions: We conclude that virus-specific CCR5+ effector memory CD4+ T cells primed by previous exposure to related viruses contribute to the control of rhinovirus.


Subject(s)
Enterovirus Infections/immunology , Enterovirus/immunology , Immunologic Memory , Th1 Cells/immunology , Adolescent , Adult , Blood/immunology , Cell Tracking , Enterovirus Infections/virology , Female , Humans , Male , Middle Aged , Nasal Mucosa/immunology , Receptors, CCR5/analysis , Young Adult
2.
Proteomics ; 16(9): 1361-75, 2016 05.
Article in English | MEDLINE | ID: mdl-26959526

ABSTRACT

Whole cell and surface proteomes were analyzed together with adhesive properties of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM) grown on the emerging prebiotic raffinose, exemplifying a synbiotic. Adhesion of NCFM to mucin and intestinal HT-29 cells increased three-fold after culture with raffinose versus glucose, as also visualized by scanning electron microscopy. Comparative proteomics using 2D-DIGE showed 43 unique proteins to change in relative abundance in whole cell lysates from NCFM grown on raffinose compared to glucose. Furthermore, 14 unique proteins in 18 spots of the surface subproteome underwent changes identified by differential 2DE, including elongation factor G, thermostable pullulanase, and phosphate starvation inducible stress-related protein increasing in a range of +2.1 - +4.7 fold. By contrast five known moonlighting proteins decreased in relative abundance by up to -2.4 fold. Enzymes involved in raffinose catabolism were elevated in the whole cell proteome; α-galactosidase (+13.9 fold); sucrose phosphorylase (+5.4 fold) together with metabolic enzymes from the Leloir pathway for galactose utilization and the glycolysis; ß-galactosidase (+5.7 fold); galactose (+2.9/+3.1 fold) and fructose (+2.8 fold) kinases. The insights at the molecular and cellular levels contributed to the understanding of the interplay of a synbiotic composed of NCFM and raffinose with the host.


Subject(s)
Bacterial Proteins/genetics , Gene Expression Regulation, Bacterial , Lactobacillus acidophilus/drug effects , Probiotics/metabolism , Proteome/genetics , Raffinose/pharmacology , Bacterial Adhesion , Bacterial Proteins/metabolism , Galactose/metabolism , Gene Ontology , Glucosyltransferases/genetics , Glucosyltransferases/metabolism , Glycoside Hydrolases/genetics , Glycoside Hydrolases/metabolism , HT29 Cells , Humans , Lactobacillus acidophilus/genetics , Lactobacillus acidophilus/growth & development , Lactobacillus acidophilus/metabolism , Molecular Sequence Annotation , Peptide Elongation Factor G/genetics , Peptide Elongation Factor G/metabolism , Prebiotics , Proteome/metabolism , Staining and Labeling , alpha-Galactosidase/genetics , alpha-Galactosidase/metabolism
3.
Crit Rev Food Sci Nutr ; 56(4): 541-90, 2016.
Article in English | MEDLINE | ID: mdl-24219323

ABSTRACT

Nutritional management of blood glucose levels is a strategic target in the prevention and management of type 2 diabetes mellitus (T2DM). To implement such an approach, it is essential to understand the effect of food on glycemic regulation and on the underlying metabolic derangements. This comprehensive review summarizes the results from human dietary interventions exploring the impact of dietary components on blood glucose levels. Included are the major macronutrients; carbohydrate, protein and fat, micronutrient vitamins and minerals, nonnutrient phytochemicals and additional foods including low-calorie sweeteners, vinegar, and alcohol. Based on the evidence presented in this review, it is clear that dietary components have significant and clinically relevant effects on blood glucose modulation. An integrated approach that includes reducing excess body weight, increased physical activity along with a dietary regime to regulate blood glucose levels will not only be advantages in T2DM management, but will benefit the health of the population and limit the increasing worldwide incidence of T2DM.


Subject(s)
Blood Glucose/physiology , Diabetes Mellitus, Type 2/diet therapy , Amino Acids/administration & dosage , Animals , Diabetes Mellitus, Type 2/prevention & control , Dietary Carbohydrates/administration & dosage , Dietary Fats/administration & dosage , Dietary Fiber/administration & dosage , Dietary Proteins/administration & dosage , Exercise , Gastrointestinal Tract/microbiology , Humans , Insulin/metabolism , Insulin Secretion , Minerals/administration & dosage , Phytochemicals/administration & dosage , Prebiotics/administration & dosage , Probiotics/administration & dosage , Vitamins/administration & dosage , Weight Loss
4.
Pediatr Allergy Immunol ; 27(8): 838-846, 2016 12.
Article in English | MEDLINE | ID: mdl-27590263

ABSTRACT

BACKGROUND: An altered compositional signature and reduced diversity of early gut microbiota are linked to development of allergic disease. We investigated the relationship between dominant Bifidobacterium species during the early post-natal period and subsequent development of allergic disease in the first year of life. METHODS: Faecal samples were collected at age 1 week, 1 month and 3 months from 117 infants at high risk of allergic disease. Bifidobacterium species were analysed by quantitative PCR and terminal restriction fragment length polymorphism. Infants were examined at 3, 6 and 12 months, and skin prick test was performed at 12 months. Eczema was diagnosed according to the UK Working Party criteria. RESULTS: The presence of B. catenulatum at 3 months was associated with a higher risk of developing eczema (ORadj = 4.5; 95% CI: 1.56-13.05, padj = 0.005). Infants colonized with B. breve at 1 week (ORadj = 0.29; 95% CI: 0.09-0.95, padj = 0.04) and 3 months (ORadj = 0.15; 95% CI: 0.05-0.44, padj = 0.00001) had a reduced risk of developing eczema. Furthermore, the presence of B. breve at 3 months was associated with a lower risk of atopic sensitization at 12 months (ORadj = 0.38; 95% CI: 0.15-0.98, padj = 0.05). B. breve colonization patterns were influenced by maternal allergic status, household pets and number of siblings. CONCLUSIONS: Temporal variations in Bifidobacterium colonization patterns early in life are associated with later development of eczema and/or atopic sensitization in infants at high risk of allergic disease. Modulation of the early microbiota may provide a means to prevent eczema in high-risk infants.


Subject(s)
Bacterial Infections/epidemiology , Bifidobacterium breve/immunology , Eczema/epidemiology , Hypersensitivity/epidemiology , Bifidobacterium breve/genetics , DNA, Bacterial/analysis , Feces/microbiology , Female , Gastrointestinal Microbiome/immunology , Humans , Infant , Infant, Newborn , Male , Probiotics , Risk , Skin Tests
5.
BMC Biochem ; 16: 26, 2015 Nov 11.
Article in English | MEDLINE | ID: mdl-26558435

ABSTRACT

BACKGROUND: ß-Mannans are abundant and diverse plant structural and storage polysaccharides. Certain human gut microbiota members including health-promoting Bifidobacterium spp. catabolize dietary mannans. Little insight is available on the enzymology of mannan deconstruction in the gut ecological niche. Here, we report the biochemical properties of the first family 5 subfamily 8 glycoside hydrolase (GH5_8) mannanase from the probiotic bacterium Bifidobacterium animalis subsp. lactis Bl-04 (BlMan5_8). RESULTS: BlMan5_8 possesses a novel low affinity carbohydrate binding module (CBM) specific for soluble mannan and displays the highest catalytic efficiency reported to date for a GH5 mannanase owing to a very high k cat (1828 ± 87 s(-1)) and a low K m (1.58 ± 0.23 g · L(-1)) using locust bean galactomannan as substrate. The novel CBM of BlMan5_8 mediates increased binding to soluble mannan based on affinity electrophoresis. Surface plasmon resonance analysis confirmed the binding of the CBM10 to manno-oligosaccharides, albeit with slightly lower affinity than the catalytic module of the enzyme. This is the first example of a low-affinity mannan-specific CBM, which forms a subfamily of CBM10 together with close homologs present only in mannanases. Members of this new subfamily lack an aromatic residue mediating binding to insoluble cellulose in canonical CBM10 members consistent with the observed low mannan affinity. CONCLUSION: BlMan5_8 is evolved for efficient deconstruction of soluble mannans, which is reflected by an exceptionally low K m and the presence of an atypical low affinity CBM, which increases binding to specifically to soluble mannan while causing minimal decrease in catalytic efficiency as opposed to enzymes with canonical mannan binding modules. These features highlight fine tuning of catalytic and binding properties to support specialization towards a preferred substrate, which is likely to confer an advantage in the adaptation to competitive ecological niches.


Subject(s)
Bacterial Proteins/metabolism , Bifidobacterium/enzymology , Dietary Fiber/metabolism , Mannans/metabolism , Mannosidases/metabolism , Models, Molecular , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Binding Sites , Catalytic Domain , Enzyme Stability , Galactose/analogs & derivatives , Humans , Ligands , Mannans/chemistry , Mannosidases/chemistry , Mannosidases/genetics , Mutagenesis, Site-Directed , Mutation , Phylogeny , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Solubility , Structural Homology, Protein , Substrate Specificity
6.
Proc Natl Acad Sci U S A ; 108(43): 17785-90, 2011 Oct 25.
Article in English | MEDLINE | ID: mdl-22006318

ABSTRACT

Probiotic microbes rely on their ability to survive in the gastrointestinal tract, adhere to mucosal surfaces, and metabolize available energy sources from dietary compounds, including prebiotics. Genome sequencing projects have proposed models for understanding prebiotic catabolism, but mechanisms remain to be elucidated for many prebiotic substrates. Although ß-galactooligosaccharides (GOS) are documented prebiotic compounds, little is known about their utilization by lactobacilli. This study aimed to identify genetic loci in Lactobacillus acidophilus NCFM responsible for the transport and catabolism of GOS. Whole-genome oligonucleotide microarrays were used to survey the differential global transcriptome during logarithmic growth of L. acidophilus NCFM using GOS or glucose as a sole source of carbohydrate. Within the 16.6-kbp gal-lac gene cluster, lacS, a galactoside-pentose-hexuronide permease-encoding gene, was up-regulated 5.1-fold in the presence of GOS. In addition, two ß-galactosidases, LacA and LacLM, and enzymes in the Leloir pathway were also encoded by genes within this locus and up-regulated by GOS stimulation. Generation of a lacS-deficient mutant enabled phenotypic confirmation of the functional LacS permease not only for the utilization of lactose and GOS but also lactitol, suggesting a prominent role of LacS in the metabolism of a broad range of prebiotic ß-galactosides, known to selectively modulate the beneficial gut microbiota.


Subject(s)
Gene Expression Regulation, Bacterial/physiology , Lactobacillus acidophilus/metabolism , Membrane Transport Proteins/metabolism , Oligosaccharides/pharmacokinetics , Prebiotics , beta-Galactosidase/metabolism , DNA, Complementary/genetics , Lactobacillus acidophilus/genetics , Microarray Analysis , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction , beta-Galactosidase/genetics
7.
BMC Genomics ; 14: 312, 2013 May 10.
Article in English | MEDLINE | ID: mdl-23663691

ABSTRACT

BACKGROUND: Probiotic bifidobacteria in combination with prebiotic carbohydrates have documented positive effects on human health regarding gastrointestinal disorders and improved immunity, however the selective routes of uptake remain unknown for most candidate prebiotics. The differential transcriptomes of Bifidobacterium animalis subsp. lactis Bl-04, induced by 11 potential prebiotic oligosaccharides were analyzed to identify the genetic loci involved in the uptake and catabolism of α- and ß-linked hexoses, and ß-xylosides. RESULTS: The overall transcriptome was modulated dependent on the type of glycoside (galactosides, glucosides or xylosides) utilized. Carbohydrate transporters of the major facilitator superfamily (induced by gentiobiose and ß-galacto-oligosaccharides (GOS)) and ATP-binding cassette (ABC) transporters (upregulated by cellobiose, GOS, isomaltose, maltotriose, melibiose, panose, raffinose, stachyose, xylobiose and ß-xylo-oligosaccharides) were differentially upregulated, together with glycoside hydrolases from families 1, 2, 13, 36, 42, 43 and 77. Sequence analysis of the identified solute-binding proteins that determine the specificity of ABC transporters revealed similarities in the breadth and selectivity of prebiotic utilization by bifidobacteria. CONCLUSION: This study identified the differential gene expression for utilization of potential prebiotics highlighting the extensive capabilities of Bifidobacterium lactis Bl-04 to utilize oligosaccharides. Results provide insights into the ability of this probiotic microbe to utilize indigestible carbohydrates in the human gastrointestinal tract.


Subject(s)
Bifidobacterium/drug effects , Bifidobacterium/genetics , Gene Expression Profiling , Oligosaccharides/pharmacology , Prebiotics , Transcription, Genetic/drug effects , Cell Membrane/drug effects , Cell Membrane/metabolism , Data Mining , Genetic Variation/genetics , Genomics , Multigene Family/genetics , Up-Regulation/drug effects
8.
Microorganisms ; 11(2)2023 Jan 28.
Article in English | MEDLINE | ID: mdl-36838294

ABSTRACT

Traditional probiotics comprise mainly lactic acid bacteria that are safe for human use, tolerate acid and bile, and adhere to the epithelial lining and mucosal surfaces. In this study, one hundred commercial and non-commercial strains that were isolated from human feces or vaginal samples were tested with regards to overall growth in culture media, tolerance to acid and bile, hydrogen peroxide (H2O2) production, and adhesion to vaginal epithelial cells (VECs) and to blood group antigens. As a result, various of the tested lactobacilli strains were determined to be suitable for gastrointestinal or vaginal applications. Commercial strains grew better than the newly isolated strains, but tolerance to acid was a common property among all tested strains. Tolerance to bile varied considerably between the strains. Resistance to bile and acid correlated well, as did VEC adhesion and H2O2 production, but H2O2 production was not associated with resistance to bile or acid. Except for L. iners strains, vaginal isolates had better overall VEC adhesion and higher H2O2 production. Species- and strain-specific differences were evident for all parameters. Rank-ordered clustering with nine clusters was used to identify strains that were suitable for gastrointestinal or vaginal health, demonstrating that the categorization of strains for targeted health indications is possible based on the parameters that were measured in this study.

9.
Proteomics ; 12(7): 1006-14, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22522807

ABSTRACT

Lactobacillus acidophilus NCFM (NCFM) is a well-documented probiotic bacterium isolated from human gut. Detailed 2D gel-based NCFM proteomics addressed the so-called alkaline range, i.e., pH 6-11. Proteins were identified in 150 of the 202 spots picked from the Coomassie Brilliant Blue stained 2D gel using MALDI-TOF-MS. The 102 unique gene products among the 150 protein identifications were assigned to different functional categories, and evaluated by considering a calculated distribution of abundance as well as grand average of hydrophobicity values. None of the very few available lactic acid bacteria proteome reference maps included the range of pI >7.0. The present report of such data on the proteome of NCFM fundamentally complements current knowledge on protein profiles limited to the acid and neutral pH range.


Subject(s)
Bacterial Proteins/analysis , Electrophoresis, Gel, Two-Dimensional/methods , Lactobacillus acidophilus/chemistry , Proteome/analysis , Proteomics/methods , Bacterial Proteins/chemistry , Bacterial Proteins/classification , Hydrogen-Ion Concentration , Proteome/chemistry
10.
BMC Microbiol ; 12: 94, 2012 Jun 06.
Article in English | MEDLINE | ID: mdl-22672382

ABSTRACT

BACKGROUND: The mucus layer covering the human intestinal epithelium forms a dynamic surface for host-microbial interactions. In addition to the environmental factors affecting the intestinal equilibrium, such as diet, it is well established that the microbiota composition is individually driven, but the host factors determining the composition have remained unresolved. RESULTS: In this study, we show that ABO blood group is involved in differences in relative proportion and overall profiles of intestinal microbiota. Specifically, the microbiota from the individuals harbouring the B antigen (secretor B and AB) differed from the non-B antigen groups and also showed higher diversity of the Eubacterium rectale-Clostridium coccoides (EREC) and Clostridium leptum (CLEPT) -groups in comparison with other blood groups. CONCLUSIONS: Our novel finding indicates that the ABO blood group is one of the genetically determined host factors modulating the composition of the human intestinal microbiota, thus enabling new applications in the field of personalized nutrition and medicine.


Subject(s)
ABO Blood-Group System , Biota , Gastrointestinal Tract/microbiology , Metagenome , Adult , Female , Humans , Male , Middle Aged
11.
Biosci Biotechnol Biochem ; 76(6): 1135-9, 2012.
Article in English | MEDLINE | ID: mdl-22790935

ABSTRACT

Different ways of treating bran by baking enzymes prior to dough making and the baking process were used to increase the amount of water-soluble dietary fiber (DF) in wheat bread with added bran. Soluble DF was extracted from the bread with water and separated from the digestible material with gastrointestinal tract enzymes and by solvent precipitation. The baking enzyme mixtures tested (xylanase and glucanase/cellulase, with and without lipase) increased the amounts of soluble arabinoxylan and protein resistant to digestion. The isolated fiber was used as a growth substrate for 11 probiotic and intestinal Bifidobacterium strains, for commensal strains of Bacteroides fragilis and Escherichia coli, and for potential intestinal pathogenic strains of E. coli O157:H7, Salmonella typhimurium, and Clostridium perfringens. Fermentation analyses indicated that the tested strains had varying capacity to grow in the presence of the extracted fiber. Of the tested probiotic strains B. longum species generally showed the highest ability to utilize the fiber extracts, although the potential pathogens tested also showed an ability to grow on these fiber extracts. In sum, the enzymes used to improve the baking process for high-fiber bread can also be used to produce in situ soluble fiber material, which in turn can exert prebiotic effects on certain potentially beneficial microbes.


Subject(s)
Bread/microbiology , Dietary Fiber/metabolism , Probiotics/metabolism , Bacteroides fragilis/growth & development , Bacteroides fragilis/metabolism , Bifidobacterium/growth & development , Bifidobacterium/metabolism , Cellulases/metabolism , Clostridium perfringens/growth & development , Clostridium perfringens/metabolism , Endo-1,4-beta Xylanases/metabolism , Escherichia coli O157/growth & development , Escherichia coli O157/metabolism , Fermentation , Food Microbiology , Food Technology , Lipase/metabolism , Plant Proteins/biosynthesis , Xylans/biosynthesis
13.
Article in English | MEDLINE | ID: mdl-23990833

ABSTRACT

Probiotics are viable by definition, and viability of probiotics is often considered to be a prerequisite for the health benefits. Indeed, the overwhelming majority of clinical studies in the field have been performed with viable probiotics. However, it has also been speculated that some of the mechanisms behind the probiotic health effects may not be dependent on the viability of the cells and, therefore, is also possible that also non-viable probiotics could have some health benefits. The efficacy of non-viable probiotics has been assessed in a limited number of studies, with varying success. While it is clear that viable probiotics are more effective than non-viable probiotics and that, in many cases, viability is indeed a prerequisite for the health benefit, there are also some cases where it appears that non-viable probiotics could also have beneficial effects on human health.

14.
Proteomics ; 11(17): 3470-81, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21751373

ABSTRACT

Lactobacillus acidophilus NCFM is a probiotic bacterium adapted to survive in the gastrointestinal tract and with potential health benefits to the host. Lactitol is a synthetic sugar alcohol used as a sugar replacement in low calorie foods and selectively stimulating growth of L. acidophilus NCFM. In the present study the whole-cell extract proteome of L. acidophilus NCFM grown on glucose until late exponential phase was resolved by 2-DE (pH 3-7). A total of 275 unique proteins assigned to various physiological processes were identified from 650 spots. Differential 2-DE (DIGE) (pH 4-7) of L. acidophilus NCFM grown on glucose and lactitol, revealed 68 spots with modified relative intensity. Thirty-two unique proteins were identified in 41 of these spots changing 1.6-12.7-fold in relative abundance by adaptation of L. acidophilus NCFM to growth on lactitol. These proteins included ß-galactosidase small subunit, galactokinase, galactose-1-phosphate uridylyltransferase and UDP-glucose-4-epimerase, which all are potentially involved in lactitol metabolism. This first comprehensive proteome analysis of L. acidophilus NCFM provides insights into protein abundance changes elicited by the prebiotic lactitol.


Subject(s)
Bacterial Proteins/metabolism , Lactobacillus acidophilus/metabolism , Proteomics , Sugar Alcohols/metabolism , Bacterial Proteins/analysis , Electrophoresis, Gel, Two-Dimensional/methods , Glucose/metabolism , Lactobacillus acidophilus/chemistry , Probiotics/metabolism , Proteomics/methods
15.
PLoS One ; 16(12): e0260765, 2021.
Article in English | MEDLINE | ID: mdl-34855861

ABSTRACT

The past two decades of research have raised gut microbiota composition as a contributing factor to the development of obesity, and higher abundance of certain bacterial species has been linked to the lean phenotype, such as Akkermansia muciniphila. The ability of pre- and probiotics to affect metabolic health could be via microbial community alterations and subsequently changes in metabolite profiles, modulating for example host energy balance via complex signaling pathways. The aim of this mice study was to determine how administration of a prebiotic fiber, polydextrose (PDX) and a probiotic Bifidobacterium animalis ssp. lactis 420 (B420), during high fat diet (HFD; 60 kcal% fat) affects microbiota composition in the gastrointestinal tract and adipose tissue, and metabolite levels in gut and liver. In this study C57Bl/6J mice (N = 200) were split in five treatments and daily gavaged: 1) Normal control (NC); 2) HFD; 3) HFD + PDX; 4) HFD + B420 or 5) HFD + PDX + B420 (HFD+S). At six weeks of treatment intraperitoneal glucose-tolerance test (IPGTT) was performed, and feces were collected at weeks 0, 3, 6 and 9. At end of the intervention, ileum and colon mucosa, adipose tissue and liver samples were collected. The microbiota composition in fecal, ileum, colon and adipose tissue was analyzed using 16S rDNA sequencing, fecal and liver metabolomics were performed by nuclear magnetic resonance (NMR) spectroscopy. It was found that HFD+PDX intervention reduced body weight gain and hepatic fat compared to HFD. Sequencing the mice adipose tissue (MAT) identified Akkermansia and its prevalence was increased in HFD+S group. Furthermore, by the inclusion of PDX, fecal, lleum and colon levels of Akkermansia were increased and liver health was improved as the detoxification capacity and levels of methyl-donors were increased. These new results demonstrate how PDX and B420 can affect the interactions between gut, liver and adipose tissue.


Subject(s)
Akkermansia/isolation & purification , Bifidobacterium animalis/chemistry , Gastrointestinal Tract/drug effects , Glucans/administration & dosage , Gram-Negative Bacterial Infections/drug therapy , Liver/drug effects , Obesity/physiopathology , Akkermansia/drug effects , Animals , Diet, High-Fat , Energy Metabolism , Feces/microbiology , Gastrointestinal Tract/microbiology , Gram-Negative Bacterial Infections/epidemiology , Gram-Negative Bacterial Infections/microbiology , Gram-Negative Bacterial Infections/pathology , Liver/microbiology , Male , Mice , Mice, Inbred C57BL , Prevalence , Probiotics/administration & dosage
16.
Curr Opin Pediatr ; 22(5): 626-34, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20733491

ABSTRACT

PURPOSE OF REVIEW: This paper summarizes recent publications on probiotics and prebiotics in allergic disease. It focuses on clinical studies of prevention or treatment of allergic disease. RECENT FINDINGS: Studies suggest a role for certain probiotics (alone or with prebiotics) in the prevention of atopic eczema. Treatment during the prenatal period appears to be important for beneficial effects. The use of probiotics for the treatment of established allergic disease is less promising, despite some positive results. A Cochrane systematic review concluded that, when the results for the different probiotic strains used in clinical trials are pooled, probiotics are not effective for the treatment of eczema. There are fewer studies of prebiotics for the treatment or prevention of allergic disease, but data suggest that prebiotic-supplemented formulas may be effective for preventing eczema in infants at high risk of developing allergic disease when breast-feeding is not possible. SUMMARY: Allergic diseases continue to increase in prevalence worldwide, and primary prevention of allergic disease has proved an elusive goal. Probiotic bacteria represent the most promising intervention for primary prevention that has been studied to date, and definitive intervention studies should now be a research priority.


Subject(s)
Hypersensitivity/prevention & control , Prebiotics , Primary Prevention/methods , Probiotics/pharmacology , Humans
17.
Biosci Biotechnol Biochem ; 74(10): 2016-21, 2010.
Article in English | MEDLINE | ID: mdl-20944426

ABSTRACT

Polydextrose is a randomly linked complex glucose oligomer that is widely used as a sugar replacer, bulking agent, dietary fiber and prebiotic. Polydextrose is poorly utilized by the host and, during gastrointestinal transit, it is slowly degraded by intestinal microbes, although it is not known which parts of the complex molecule are preferred by the microbes. The microbial degradation of polydextrose was assessed by using a simulated model of colonic fermentation. The degradation products and their glycosidic linkages were measured by combined gas chromatography and mass spectrometry, and compared to those of intact polydextrose. Fermentation resulted in an increase in the relative abundance of non-branched molecules with a concomitant decrease in single-branched glucose molecules and a reduced total number of branching points. A detailed analysis showed a preponderance of 1,6 pyranose linkages. The results of this study demonstrate how intestinal microbes selectively degrade polydextrose, and provide an insight into the preferences of gut microbiota in the presence of different glycosidic linkages.


Subject(s)
Colon/microbiology , Glucans/chemistry , Glucans/metabolism , Glycosides/chemistry , Metagenome , Fermentation , Humans
18.
Cell Rep ; 30(2): 351-366.e7, 2020 01 14.
Article in English | MEDLINE | ID: mdl-31940481

ABSTRACT

Human rhinoviruses cause the common cold and exacerbate chronic respiratory diseases. Although infection elicits neutralizing antibodies, these do not persist or cross-protect across multiple rhinovirus strains. To analyze rhinovirus-specific B cell responses in humans, we developed techniques using intact RV-A16 and RV-A39 for high-throughput high-dimensional single-cell analysis, with parallel assessment of antibody isotypes in an experimental infection model. Our approach identified T-bet+ B cells binding both viruses that account for ∼5% of CXCR5- memory B cells. These B cells infiltrate nasal tissue and expand in the blood after infection. Their rapid secretion of heterotypic immunoglobulin G (IgG) in vitro, but not IgA, matches the nasal antibody profile post-infection. By contrast, CXCR5+ memory B cells binding a single virus are clonally distinct, absent in nasal tissue, and secrete homotypic IgG and IgA, mirroring the systemic response. Temporal and spatial functions of dichotomous memory B cells might explain the ability to resolve infection while rendering the host susceptible to re-infection.


Subject(s)
B-Lymphocytes/immunology , Cross Reactions/immunology , Immunoglobulin G/immunology , Immunologic Memory/immunology , Rhinovirus/immunology , Humans
19.
BMC Microbiol ; 9: 245, 2009 Nov 30.
Article in English | MEDLINE | ID: mdl-19948011

ABSTRACT

BACKGROUND: Prebiotics are non-digestible food ingredients believed to beneficially affect host health by selectively stimulating the growth of the beneficial bacteria residing in the gut. Such beneficial bacteria have been reported to protect against pathogenic infections. However, contradicting results on prevention of Salmonella infections with prebiotics have been published. The aim of the present study was to examine whether S. Typhimurium SL1344 infection in mice could be prevented by administration of dietary carbohydrates with different structures and digestibility profiles. BALB/c mice were fed a diet containing 10% of either of the following carbohydrates: inulin, fructo-oligosaccharide, xylo-oligosaccharide, galacto-oligosaccharide, apple pectin, polydextrose or beta-glucan for three weeks prior to oral Salmonella challenge (107 CFU) and compared to mice fed a cornstarch-based control diet. RESULTS: The mice fed with diets containing fructo-oligosaccharide (FOS) or xylo-oligosaccharide (XOS) had significantly higher (P < 0.01 and P < 0.05) numbers of S. Typhimurium SL1344 in liver, spleen and mesenteric lymph nodes when compared to the mice fed with the cornstarch-based control diet. Significantly increased amounts (P < 0.01) of Salmonella were detected in ileal and fecal contents of mice fed with diets supplemented with apple pectin, however these mice did not show significantly higher numbers of S. Typhimyrium in liver, spleen and lymph nodes than animals from the control group (P < 0.20).The acute-phase protein haptoglobin was a good marker for translocation of S. Typhimurium in mice. In accordance with the increased counts of Salmonella in the organs, serum concentrations of haptoglobin were significantly increased in the mice fed with FOS or XOS (P < 0.001). Caecum weight was increased in the mice fed with FOS (P < 0.01), XOS (P < 0.01), or polydextrose (P < 0.001), and caecal pH was reduced in the mice fed with polydextrose (P < 0.001). In vitro fermentation in monocultures revealed that S. Typhimurium SL1344 is capable of fermenting FOS, beta-glucan and GOS with a corresponding decline in pH. CONCLUSION: Supplementing a cornstarch-based rodent diet with 10% FOS or XOS was found to increase the translocation of S. Typhimurium SL1344 to internal organs in mice, while 10% apple pectin was found to increase the numbers of S. Typhimurium in intestinal content and feces.


Subject(s)
Prebiotics , Salmonella Infections/physiopathology , Salmonella typhimurium/physiology , Animals , Body Weight/physiology , Cecum/physiology , Dietary Carbohydrates/administration & dosage , Feces/microbiology , Fermentation/physiology , Haptoglobins/analysis , Hydrogen-Ion Concentration , Mice , Mice, Inbred BALB C , Salmonella Infections/microbiology , Salmonella typhimurium/isolation & purification , Salmonella typhimurium/metabolism , Spleen/cytology
20.
FEMS Immunol Med Microbiol ; 53(1): 18-25, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18336547

ABSTRACT

Faecal and serum samples were collected over a period of 6 months from 55 institutionalized elderly subjects, who were enrolled in a double-blind placebo-controlled study. Participants were randomized in one of the three treatment groups: intervention (two probiotic Bifidobacterium longum strains: 2C and 46), placebo and commercial control (Bifidobacterium lactis Bb-12). The faecal Bifidobacterium microbiota was characterized by genus and species-specific PCR. Serum levels of the cytokines IL-10, tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1 were determined by enzyme-linked immunosorbent assay. Each participant harboured on average approximately three different bifidobacterial species. The most frequently detected species were B. longum, Bifidobacterium adolescentis and Bifidobacterium bifidum. Depending on the treatment, the intervention resulted in specific changes in the levels of certain Bifidobacterium species, and positive correlations were found between the different species. Negative correlations were observed between the levels of Bifidobacterium species and the pro-inflammatory cytokine TNF-alpha and the regulatory cytokine IL-10. The presence of faecal B. longum and Bifidobacterium animalis correlated with reduced serum IL-10. The anti-inflammatory TGF-beta1 levels were increased over time in all three groups, and the presence of Bifidobacterium breve correlated with higher serum TGF-beta1 levels. This indicates that modulation of the faecal Bifidobacterium microbiota may provide a means of influencing inflammatory responses.


Subject(s)
Bifidobacterium/immunology , Gastrointestinal Tract/immunology , Gastrointestinal Tract/microbiology , Probiotics/pharmacology , Aged, 80 and over , Bifidobacterium/growth & development , Colony Count, Microbial , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Double-Blind Method , Feces/microbiology , Female , Humans , Interleukin-10/blood , Male , Polymerase Chain Reaction , Statistics, Nonparametric , Transforming Growth Factor beta/blood , Tumor Necrosis Factor-alpha/blood
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